1. Field of the Invention
The present invention relates to a structure for an upper body section of a vehicle body of the type having a generally U-shaped roof side gutter extending in the lengthwise direction of the vehicle body along each side of a roof panel to which an upper body side frame is secured.
2. Description of Related Art
Some types of vehicle bodies have upper body sections having a structure in which a generally U-shaped roof side gutter, opening upward, is interposed between a roof and each side frame. This generally U-shaped roof side gutter is defined by a U-shaped gutter rail comprising an inside half of gutter rail integrally formed with a roof panel and an outside half of gutter rail integrally formed with a side frame panel. Such an upper body section is reinforced by a roof reinforcement beam extending in a transverse direction of the vehicle body between left and right center pillars and secured to the roof panel. The inside half of the gutter rail is laid to overlap the outside half of the gutter rail and located on the inner side of an inside pillar member of the center pillar.
In vehicle bodies having upper body sections of the type having no roof side gutter structure, as shown in Japanese Unexamined Utility Model Publication No. 1-57967, there is provided a roof side rail, extending along a top end of the upper body section, to which a roof panel, a roof reinforcement beam and a center pillar are secured. The roof side rail, at a section where an end of the roof reinforcement beam is connected, is covered by inner and outer brace members to form a closed cross section.
In the event of a lateral or "flank" collision, the energy of an impact reaches a center pillar via the side body. If the center pillar and a body section surrounding the center pillar do not have a sufficient structural strength or rigidity, then it is hard to prevent the vehicle body from deformation of the center pillar which can possibly injure a passenger in the event of a flank collision. In vehicle bodies of the type having a U-shaped roof side gutter, stress due to the energy of an impact caused upon a flank collision concentrates at the roof side gutter before the energy reaches the roof reinforcement through the center pillar. Because the roof side gutter is formed by two separate gutter rail sections, namely inside and outside halves of gutter rail sections, deformation of the center pillar due to a flank collision is enhanced.